Illuminated display device for educational purposes



1 Oct. 10, 1944.

E; s. DUDLEY 2,360,212

ILLUMINATED DISPLAY DEVICE FOR EDUCATIONAL PURPOSES Filed Dec. 17, 1942 2 Sheets-Sheet 1 1' Mil W' nn. I 2 1 III I A A A "A f Oct. 10, 1944. E. G. DUDLEY 2,360,212 ILLUMINATED DISPLAY DEVICE FOR EDUCATIONAL PURPOSES Filed Dec. 17, 1942 2 Sheets-Sheet 2 oooooboooo oooooooooo Inventor Atlorneys Patented Oct. 10, 1944 ILLUMINATED DISPLAY DEVICE FOR EDUCATIONAL PURPOSES Eric Gordon Dudley, Worcester Park, England Application December 17, 1942, Serial No. 469,339 In Great Britain January 1, 1942 3 Claims.

This invention relates to illuminated display devices of the kind which comprises a glass or other translucent panel adapted to be illuminated from the rear by a lamp or lamps.

The object of the present invention is to provide an improved device of the character above indicated which is particularly designed for educational purposes to replace blackboards for teaching in order to avoid the glare or light refiections and other disadvantages which frequently prevent the pupils or a considerable section of them from seeing what is written upon an ordinary blackboard.

The present invention is arranged to avoid the known disadvantages of blackboards and consists in a drawing display board for educational purposes comprising a rectangular cabinet having a vertical front wall consisting of a removable pane of ground glass or other translucent material capable of receiving drawings or other markings in a material relatively opaque to light, a plurality of controllable lighting devices disposed A at th rear of said front wall, and a group of cellular compartments each capable of independent illumination located at the rear of said front wall.

According to the preferred form of the invention, a second pane of unground glass or like sheet is disposed behind and spaced apart from the said pane of translucent material so that pre-prepared charts, diagrams and the like formed as translucent rolls mounted on rollers disposed on the sides of the cabinet, can be fed between the said panes, means being also provided for unwinding the roll from one roller and winding it upon another roller and the diagrams on the rolls being mad to coincide with the arrangement of cellular compartments.

In order that the invention shall be better understood, reference is made to the accompanying drawings wherein is shown a preferred embodimgnt of the invention.

Referring to the drawings:

Fig. 1 shows the perspective front elevation of an assembled unit.

Fig. 2 is a plan of the cabinet.

Fig. 3 is a vertical sectional elevation.

Fig. 4 shows details of the cellular construction of the cabinet and the electrical wiring.

Fig. 5 shows diagrammatically the details of the roll Winding gear.

Fig. 6 shows detail of roller bracket.

Referring to the drawings and to Fig. 1, the cabinet I is formed from any convenient material such as ply wood or the like. It is preferably rectangular, as shown, and of a depth suificient to house a cellular unit 2. In the form shown the cabinet is fitted with a front display board 3 formed from ground glass, plastic or equivalent suitable translucent material, capable of receiving chalk or pastel drawings or representations made in a material which is relatively opaque to light. This front board is mounted on bearers 4 and atthe top is secured to the cabinet by means of a lid 5 hinged at 6 and secured in position by a finger operated hook I or equivalent.

In an alternative form the said front board may have a set of bearers 4 at top and bottom, provided care is taken to have no light emission at the edges. The cabinet I is formed with cellular compartments of which a series 2 are applied to the cabinet as a drawer (see Fig. 2)

resting upon side bearers 3 (see Figs. 2 and 3). 7

These cellular compartments are each provided with an electric lamp 9 or like means of illumination which lamps are connected by conductors It] to a switching device I I capable of controlling the'illumination or light extinction of any one of the cells. In the form shown the multicellular compartment 2 is positioned at the top of the cabinet, leaving a large cell area I2 for receiving larger pictorial matter than that capable of being portrayed upon the smaller cells 2. Mounted adjacent the side of the cabinet are rollers l3 adapted to receive rolls M of pre-prepared educational matter, which are printed or otherwise impressed on paper, linen or other suitabl translucent medium. When these rolls are employed,

I the cabinet is preferably provided with a second sheet of glass 3A, see Fig. 3, spaced apart from the front sheet 3, and the fabric of the roll is passed between the two sheets and wound on to a corresponding roller l3 mounted on the opposite side of the cabinet. The rollers l3 are provided with an extension spindle l5, see Fig. 5, which has a bevel wheel l6 meshing with a bevel wheel l1 fast on shaft Hi, the said shaft l8 being provided with a handle l9 at one end. The shaft I8 is mounted in bearings 20 and the said shaft carries at the end remote from the handle a second bevel wheel l'la which by movement of th shaft, by

means of the handle 19, can be drawn into or out of gear with the opposed roller bevel wheel, so that either roller can be rotated at will to onwind or off-wind. This mechanism is not, per se new, but is a convenient means for traversing the prepared illustrated matter across the fac of the cabinet plate. The rollers are mounted at their upper and lower ends in bearing brackets 2| and 23 respectively, each bracket 2| comprising from the top bearing 2|.

. class as silhouettes.

a flat plate'secured to the top of the cabinet by screws as shown in Fig. 2 and having a hole to receive the upper end of the respective roller. The chart roller I 3 at its base is provided with an extension spindle l5, see Fig. 6, which keys to the lower end of the roller l3, said spindle having a flange l5a supported on the bearing 23. The bearing 2 3 comprises a base portion 23* secured by bolts 23 to the respective vertical end Wall of the cabinet, and alcap 22 which is hinged at 24 to the base portion and is normally held against the base portion by a thumb screw 25, the base portion and cap having semi-circular bearing portions to embrace the spindle l5. To

change the rolls, the cap 22 of bearing 23 is hinged backward and the bevel wheel IT drawn out of mesh with the bevel wheel [6, allowing the spindle l5 and. roller with chart to be withdrawn In arranging the light eiTects it is preferable that the lamps 9 give a difiused light for Which purpose reflectors are provided and difiusion plates 21 arranged in the larger cell l2 so that the utmost illumination is provided evenly over the area of said cell. This is more important in th larger cell [2 than in the small cells 2.

Openings in the cabinet I may be provided with flap-door closures 26 as shown in Fig. 1, also ventilators may be provided in the roof in the case of large cabinets or where a large number of lamps are employed.

- The operation of the invention is as follows: The teacher portrays indicia of the information he desires the class to receive in chalk or pastel upon the ground surface of the translucent glass front board, which indicia then appear to the With pre-prepared designs these may be made upon the paper rolls and be in readiness to exhibit to the class. On the other hand with the small cellular devices, figures may be presented to the class for multiplication or division or algebraical symbols may be used. The teacher can ask for addition or subtraction and after an interval obliterate, or leave the numbers first presented visible, and then flash the answer on the board. Such method has the advantage of stimulating mental eifort by the pupil while the teacher has an almost effortless task and can be substantially free to observe the response to his efforts.

For geographical lectures any portion of the globe can be portrayed on the paper chart and differently coloured as may be required.

Coloured lamps or lighting effects may be used as required and give an educative value. Thus decimal figures can be made distinct from whole numbers, or minus numbers given in one colour and plus numbers in another. Th device may be used both for day and night, and in fact at 10 matter. The matter, such as shown on the chart is normally divided into sections, each capable of producing a picture, and indications may be made on the charts to form stopping points covering the front area of the display board.

I claim:

1. A drawing display board for educational purposes, comprising a rectangular cabinet, a translucent front wall to said cabinet, 2. second translucent wall disposed slightly to the rear of saidfront wall, charts mounted upon rollers disposed at either side of said cabinet, means for progressing said charts across the cabinet between said translucent. walls. a plurality of controllable lighting devices disposed at the rear of said translucent walls, and a group of cellular compartments each capable of independent illumination disposed at the top and to therear of said translucent walls.

2. A drawing display board for educational purposes, comprising a rectangular cabinet, a

double glass wall at the front of said cabinet, the outer member of said wall being adapted to receive markings in opaque material, a vertical roller at each side of said cabinet adapted to support charts which are progressed across the front of the cabinet between said double walls, hand operating means for actuating said rollers, a plurality of controllable lighting" devices disposed at the rear of said double glass walls, and a group of cellular compartments each capable of independentilluminaticn disposed at the top and to the rear of said double glass walls.

3. A drawing display board for educationalpurposes, comprising a rectangular cabinet, two parallel translucent panes forming the front wall of said cabinet and adapted to receive markings in opaque material, a vertical roller at each side of said cabinet adapted to support a chart which extends between said translucent panes, hand operated mechanical means for winding said chart off one roller and onto th other, a plurality of controllable lighting devices disposed behind said front wall and in the base of said cabinet, reflectors and diffusion plates adapted to cooperate with said lighting devices, a horizontal partition in said cabinet, a group of cellular compartments disposed above said partition and behind said front wall, and means for independently illuminating said compartments.

' ERIC GORDON DUDLEY. 

